Case Report
Recurrent chemical pancreatitis
complicating choledochal cystic disease
Edgar Pullicino
Case report
A seventeen year old lady presented with a twelve year
history of self-limiting attacks of severe epigastric pain,
associated with occasional fever, normal total white cell
count (WCC), normal or mildly elevated serum alanine
transaminase (ALT) (13-200iu/l) and variable hyperamylasaemia
(127-460iu/l). At age 5 years, abdominal ultrasonography had
shown non-cystic dilatation of the intrahepatic and extrahepatic
biliary system without choledocholithiasis. Despite endoscopic
sphincterotomy of a normal ampulla with extraction of bile duct
stones at age eleven years, followed by laparoscopic resection
of a dilated gall bladder, the attacks increased in frequency.
Subsequent endoscopic retrograde cholangio pancreatography
(ERCP) confirmed biliary dilatation in the absence of stones
but the pancreatic duct was poorly outlined. At age 15 years a
magnetic resonance cholangiopancreatogram (MRCP) showed
generalised dilatation of the extrahepatic biliary tree involving
the common hepatic duct and the porta hepatis with a large
elongated choledochal cyst arising out of the lateral wall of
the common bile duct (CBD). These findings are best seen in a
coronal view (Figure 1) which also shows a normal pancreatic
duct joining the CBD about 15mm proximal to the level of
the ampulla. This suggests a long common pancreatobiliary
channel running through the pancreatic head before entering
the duodenal wall (Figure 2).
The patient underwent excision of the dilated biliary tract
above the anomalous pancreaticobiliary junction with Roux en
Y hepatico-jejunostomy. A small cystic lesion in the jejunal wall
was also excised. Histology of the resected specimens showed
mildly inflamed choledochal malformations with no dysplasia.
Postoperative recovery was uneventful. Follow up MRCP
surveillance for neoplasia at six month intervals showed a patent
hepatico-jejunostomy and an unchanging filling defect in the
intapancreatic bile duct stump remnant with anterior meniscal
indentation typical of a trapped air bubble (Figure 3).
Key words
Choledochal cysts, hyperamylasaemia,
hepaticojejunostomy, pancreatitis
Edgar Pullicino FRCP (Lond), PhD
Department of Medicine (Gastroenterology),
Mater Dei Hospital, Msida
Email: pullicinoe@gmail.com
Malta Medical Journal Volume 20 Issue 02 June 2008
Figure 1: Coronal MRCP image showing gross dilation of
intrahepatic and extrahepatic biliary tree (B), choledochal
cyst (CC), pancreatic duct (PD), confluence of biliary and
pancreatic ducts (C) at about 15 mm (double arrowed line)
proximal to the duodenal wall (D).
39
Table 1: Simplified Todani Classification of bile
duct cysts
Type I
Extra hepatic duct segmental
cylindrical or diffuse dilatation
Type II
Extra hepatic duct
diverticulum cyst
Type III
“Choledochoceles” of the distal
(intraduodenal) position
of the CBD
Type IVA
Multiple cysts of intra hepatic +
extra hepatic ducts
Type IVB
Multiple cysts of extrahepatic ducts
Type V
Single or multiple cysts
of intrahepatic ducts
Discussion
Choledochal cysts are rare congenital malformations of
the biliary tree, affecting mostly children and young adults
that follow defective epithelialisation or recanalisation of the
embryonic biliary plate. Biliary dilatation has been attributed to
congenital weakness of the bile duct wall although hypertonicity
of the sphincter of Oddi may coexist. 1 Choledochal cysts
may present in infancy as obstructive jaundice that must be
differentiated from biliary atresia, or intermittent cholangitis in
childhood. The finding of gross extrahepatic bile duct dilatation
that persisted in our patient despite sphincterotomy and stone
removal was highly suggestive of a predominantly Type I
Figure 2: Anatomy of long pancreatobiliary common
channel (CC) due to confluence of pancreatic dust (PD) and
common bile duct (CBD) in pancreas at distance of more
than 10 mm above ampulla of Vater.
40
choledochal cyst disease, the commonest type of choledochal
cyst according to the Todani classification2 (Table 1).
The patient’s repeated attacks of hyperamylasemia and
epigastric pain without gross elevation of WCC and ALT is
now better understood. High anomalous insertion of the
pancreatic duct into the CBD is now recognised as a frequent
radiologic finding in choledochal cystic disease.3 The absence
of a protective pancreatic duct sphincter allows free drainage
of pancreatic juice into bile. Chemical cholangitis and bile
duct epithelial injury may result from conversion of biliary
phosphatidyl choline into lysophosphatidylcholine by pancreatic
lipase A2.4 This admixture is also associated with a chemical
self-limiting pancreatitis.
MRCP which uses very heavily T2-weighted sequences
to image, serially and non invasively, the anatomy of the
pancreatobiliary tree, is rapidly gaining popularity over ERCP.5
Axial and coronal reconstructions allow confident diagnosis
and timely referral to a specialised hepatobiliary surgical unit.
MRCP permits safe serial screening for malignant complications
in the post operative years when ERCP is often made difficult
by surgery.
Excision of as much of the ectatic or cystic extra hepatic
biliary tree and restoration of biliary drainage using a Roux en
Y hepaticojejunostomy to limit biliary reflux has replaced the
older drainage procedures such as choledochoduodenostomy
which have a high re-operation rate due to poor healing of the
fibrous cyst walls. Failure to excise dilated biliary channels
predisposes to recurrent cholestasis and does not remove the
main source of dysplasia or malignancy.
The incidence of malignant transformation, usually
adenocarcinoma is 14-18% in adults over the age of 20 years
and reaches 50% at age 50 years. Most cancers are attributed
to mitogenic bile. They occur in the choledochal cysts (58%) or
Figure 3: Postoperative follow-up axial MRCP image
showing air in intrapancreatic CBD stump with anterior
meniscus shaped air-fluid level.
Malta Medical Journal Volume 20 Issue 02 June 2008
gall bladder (40%)6, and are usually not associated with any
biliary stones. A strong association between the frequent finding
of an associated anomalous pancreatic biliary duct junction and
gall bladder carcinoma has led different authors to advocate
prophylactic cholecystectomy.7 Malignant transformation is
reported less frequently in patients undergoing resection as
compared to drainage procedures.8 Regular tumour surveillance
by MRCP is recommended in all operated patients.
Conclusions
Recurrent abdominal pain in young patients associated with
hyperamylasaemia and dilatation of the extrahepatic biliary
system which persists despite endoscopic sphincterotomy
and clearance of biliary calculi requires confirmation of Type
I choledochal cystic disease with anomalous pancreatic duct
drainage, preferably by MRCP, before consideration of cyst
excision with Roux en Y hepaticojejunostomy followed by
periodic surveillance for malignancy of the biliary tract.
Malta Medical Journal Volume 20 Issue 02 June 2008
References
1. Craig AG, Chen LD, Saccone G, Chen J, Padbury R, Toouli J.
Sphincter of Oddi dysfunction associated with choledochal cyst.
Journal of Gastroenterology and Hepatology. 2001;16:230-4.
2. Todani T, Watnabe Y, Narasue M, Tabuchi K. Congential bile
duct cysts: classification operative procedures and review of 37
cases including cancer arising from choledochal cysts. Am J Surg.
1977;134:263.
3. O’Neil JA. Choledochal Cyst. Curr Probl Surg. 1992;29:361-410.
4. Shimada K, Yanagisawa J, Nakayama F. Increased
lysophosphatidyl choline and pancreatic enzyme content in
bile of patients with anomalous pancreatobiliary ductal union.
Hepatology 1991; 13: 438–44.
5. Yamataka A, Kuwatsuru R, Shima H, Kobayashi H, Lane G,
Segawa O et al. Initial experience with non breath holding
magnetic resonance cholangiopancreatography: a new non
invasive technique for the diagnosis for choledochal cysts in
children. J Paediatr Surg. 1997;32:1560-2.
6. Lu SC, Debian KA. Cystic disease of the biliary tract. In: Yamada
T et al., editors. Textbook of Gastroenterology 4th Ed. Lippincott,
William and Wilkins 2003. p. 2232.
7. Chijiiwa K, Kimura H, Tanaka M. Malignant potential of the
gall bladder in patients with anomalous pancreatobiliary ductal
function, the difference in risk between patients with and without
choledochal cyst. Int Surg. 1995;80:61-4.
8. Visser BC, Suh I, Way LW. Congenital choledochal cysts in adults.
Arch Surg. 2004;139:860-2.
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